New Physics behind the Standard Model's door?

We review the main reasons pushing us beyond the SM and we argue in favor of new physics at the electroweak scale (hence experimentally accessible at present or near{future machines). We focus on the appealing possibility that such new physics is given by a supersymmetric (SUSY) extension of the SM. We discuss the minimal case, Constrained Minimal Supersymmetric SM, and more general (maybe more natural) cases where some of the drastic assumptions of the CMSSM are dropped. In particular, in these lectures we focus on CP violation and its relation to flavor physics in the SUSY context. CP constrains the low{energy SUSY extensions of the SM, but, at the same time, it provides new powerful tool for indirect SUSY searches.